WRIGHT AXD LUFF OK THE ALKBLOIDS OF THE ACONITES. 387

XLTT.-The A l ldo%h of the Aconites, Part IV. The Alkaloids of Japanese A c o r d e Roots.

By C. It. ALDER WRIGHT and A. P. LUFF (Appendix by C. R. ALDER WRIGHT and A. E. MENKE).

5 1, Isolation of Crystallisuble L41?doid.

I ~ R I N G the past two or three years several importations of aconite roots have been made from Japan. Whetlier these consist of one single species or of several mixed together does not seem t o be certain, nor is the nature of the predominant species clear. According t o the observations of Mr. E. M. Uolmes, the roots met with commercially appear to be wholly or almost entirely of one kind, and that different i n certain respects from German A . Napellus roots. That the root's hitherto imported arc actually uniform in quality and different from

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9.

View Article Online / Journal Homepage / Table of Contents for this issue

385 WRIGHT AND LUFF ON THE

both A. NapeZZics and A . Fwox is rendered probable by the results detailed below ; b u t how far this may be due ta climatic influences, and how far it indicates difference of species, is a t present not very clear.

The observations of most manufacturers and pharmacists who have had occasion to examine cursorily or in detail these Japanese roots, point either to.their being richer in active ingredients than the A . Na- pe7Zus and A . Ferox roots ordinarily met with in commerce, o r to their containing a more active alknlo'id. Not only is the dust produoed in grinding and pulverising much more irritating than that of ordinary aconite roots, but the effects produced on the operator whilst preparing liniments, &c., from the Japanese root, and the irritating action of the liniment on the skin, are, according to Gerrard, far greater than when ordinary aconite, roots are employed, so Chat i t is not safe to substitute Japanese roots for the ordinary kinds in the preparation of pharma- ceutical tinctures, &c.

A preliminary exaniination of these roots was made some two years ago by Dr. Paul and Mr. Kingzett (Yharw~. J. Tram., Sept. I , 1877, 172 ; Yearbook qf Phnrmacy, 1877, 469), wlio obtained from nearly 4 kilos. of roots nearly 7.2 grams of alkalo'ids soluble in ether, partly crystallised, partly varnish-like. This yield, = about 0.18 per cent., is considerably superior to that obtained by one of us from a large batch (2 cwts) of A. XapeZZus roots, viz., about 0.07 per cent. of alka- loids sduble in ether (Par t I, this Journal, 1877 [l], 143) ; whence it would seem probable that the greater pohencg of the Japanese roots is due rather to i t s containing more of the active ingredient than to this latter being intrinsically more energetic physiologically. The small quantity of crystallised substance obtained in a pure condition by Paul and Kiagzett grevenhcd their studying the properties of the alka- lojid and its derivatives as tlioroughly as might be desired. They describe it as a well cr-ystallised base, infusible a t 100" (its melting point was not determined), giving the following numbers on analysis : carbon, 62.926 ; hydrogen, 7.900 and 7.726 ; nitrogen (by volume) 2.567 ; and not forming any crystallised salts, although many and varied attempts to prepsre them were made. The molecular weight was not controlled by the formation of a gold salt, &c. (probably through insnfficiency of material) ; hence, regard being had to the probable imperfect accuracy of nitrogen determinations by volume, it is evident that the formula deduced by them from the above numbers (viz., C,,H4,N0,, requiring carbon, 63-38 ; hydrogen, i .83 ; nitrogen, 2*55) , can only be regarded as an apppoximation to the truth, especially as this formula requires not only more hydrogen than that found in one of the two determinattions, but slightly more than that given by the mean of these two. As pointed out by one of us during the discussion

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

ALKALOIDS OF THE ACONITES. 389

on the paper, the numbers obtained and mast of the properties of the crystallised alkaloi’d are quite compatible with the possibility of this base being simply pseudaconitine, C9,H,,NO,,, which requires carbon, 62.88 ; hydrogen, 7.13 ; nitrogen, 2.04 ; numbers almost exactly the same as those deducible from Paul and Kingzett’s analysis, after making allowance for trhe probable excesses of hydrogen and nitrogen found, whilst the difficulty in forming crystallised salts, noticed by Paul and Kingzett, is precisely that noticed with pseudaconitine, +,he gold salt and nitrate of which are the only salts yet obtained crystallised ; the preparation s f these crystalhe salts, moreover, requires peculiar manipulation, the nature of which was not known at the time of the publication of their results (Part 11). On the other h.and, the crys- tallisability of the base obtained by Paul and Kingzett appeared to them to be m w h higher than that of pseudaconitine, wherefore they were disposed to regard it as a distinct alkalo’id. This view, moreover, is borne out by the fact observed by them, that on boiling their base with dilute sulphwic acid a liquid was obtained capable o€ reducing Fehling’s solution. Now pseudaconine, producible in this way from pseudaconitine, does not reduce Fehling’s solution, although sconine, the corresponding snponification-product of aconitine, does do so. It hence appears at least probable that the base examined by Paul and Kingzett was a saponifiable one like aconitine and pseudaconitine, in which case a simple explanation is given of the circumstance aoticed by Paul and Kingzett, that the mother-liquor of the base when recrys- tallised froan hot dilute alcohol contained an organic saZt of an alkalo’id in solution. Doxbtless the original alkaloid became partially saponi- fied by the hot aqueous liquid, just as pseudaconitine does under similar conditions (Part 11). Paul and Kiageett, however, considered that the occurrence of a salt in the mother-liquors pointed to the solu- tion by ether of this salt (possibly aconitate) during the extraction of the alkalojids ; a most unlikely thing to happen, considering that the ether was applied in presence of excess of alkaline bicarbonate, which must inevitably have decomposed such a salt, forming the eorrespond- ing sodium salt., carbon dioxide, and the free alkaloid.

Paul and Kingzett having, through various circumstances, relin- quished the further investigation of these Japanese aconite roots, and the nature of the contained alkalojids being thus in an uncertain state, we have, at the request of the Pharmaceutical Conference (to which our thanks are due for several money grants for carrying out the following experiments, as well as those detailed in Parts I, 11, and III) , made a careful examination of the subject. Our results (obtained with two different batches of roots), as well as some further resnlts (obtained with a third batch by one of US and Mr. A. E. Menke) de- tailed in an appendix to this paper, indicate that the view held by

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

390 \TF(IGIIT -1Yn LUFF OX THE

Paul and Eingzett that Japanese aconite roots contsin an alkalojId different from both aconitine and pseudaconitine, and peculiar to them- selves, is correct. Practically identical analytical numbers were obtained , not only with all three batches of roots, but also with each fraction into which each batch of crystallisable alkalo'id was fractionated, with a view to finding out whether the substance obtained was a mixture of more than one base. These numbers, whilst not far removed from the percentages obtained by Paul and Kingzett, lead to a formula consider- ably different from that assigned by them, the molecixlar weight being much higher. The alkaloi'd, which thus appears to be the oniy crys- tallisable one contained, presents many resemblances to aconitine, and, like that base, splits up into benzoic acid and a derivative closely re- sembling aconine. This latter saponification-product reduces Fehling's solution, whence it appears probable that the subst'ance extracted by Paul and Kingzett was actually the same as that obtained log us. It is difficult, however, to understand why in that case Paul and Kingzett failed to obtain crystallised snlts, as every specimen of base obtained by us readily yielded a well crystallised nitrate hydrochloride a n d hydrobromide on simply stirring a pnlveriscd crFstal in a watch glass with a little dilute acid. Solution to a clear fluid a t first took place, and on further stirring, a crystallised magma of the respective salt was formed, just as with aconitine.

The firct batch of roots examined bg us was obtained from Mcssrs. Wright, Layman, and Umney : ahout 14 kilos. of ground root were per- colated with alcohol acidulated with taibtaric acid, 1 part of acid per 100 of roots being emplcyed : the percolate was evaporated to a small bulk, diluted with water, strained from precipitated resinous matter, shaken with ether whilst still acid to remove remaining resinous matter, and then rendered slightly alkaline d h sodium carbonate, and shaken repeatedly with ether, the ethereal solutions being shaken with aqueous tartaric acid, and used over again. After some six treatments with an equal bulk of ether, b u t little alkaloid was dissolved out, and this little appeared to be non- crystalline ; the alkaline liquors, however, con- tained (as remarked by Paul and Kingzett, and like the corresponding liquors from A . NapeZhis-Part I) some amount of alkalojidnl matter in solution ; this was examined as described below (§ 5), but appeared to contain only non-crystalline basic matter. The crude tartaric acid solution of bases thus obtained was treatecl with sodium carbonate and fresh ether, and the ethereal solution allowed to evaporate spon- taneously : a copious crop of crystals was obtained with a quantity of viscid alkaloidal matter, readily soluble in alcohol and ether. By filter- pumping and washing the crystals were obtained pretty free from amorphous bases : the filtrates on spontaneous evaporation deposited n few inore crystals, too small in quantity for examination ; finally them

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

ALKALOIDS O F THE ACONITES. 391

were obtained about 12 grams of cr.ystallised base and 25 of resinous basic matter from the filtrates, corresponding to about 0.08 per cent. of crystals, and 0.17 per cent. of amorphous bases, = 0.25 per cent. i n all, or somewhat more than was obtained by Paul and Kingzett, who obtained a total yield of about 0.18 per cent.

The first crystals deposited were purified by several crFstallisations from ether, and were then marked (A) : on analysis they yielded num- bers close to those required for apo-aconitine, whence we were a t first inclined to suppose that the alkalo'id originally present was aconitine, and that it had been partially dehydrated during extraction by the tartaric acid : this view, however, was negatived by the fact that just the same numbers were obtained after converting crjstals (A) into hydro- bromide, recrystallising the salt, and regenerating the alkaloid (Speci- men B) ; whilst no change was introduced by repeating the purifica- tion by again converting into hydrobromide, crystallising the salt, and regenerating tlhe base (Specimen C). Moreover the mother- liquors of the first crop of crjstals of hydrobromide were treated with sodium carbonate and ether, and the base that crystallised from the ether examined (Specimen D). In all four cases numbers were ob- tained which, though not f a r from those required for apo-aconitine, were yet sufficiently removed therefrom to indicate a difference, the carbon and especially the hydrogen found being uniformly higher than the values got on examination of pure npo-aconitine (Part ITI).

The second batch of roots was worked np by Messrs. Hopkin and Williams in the same way as that above deFcribed, being percolated with alcohol acidulated with tartario acid (1 part per 100 of roots). The bases soluble in ether finally obtaincci were sent to us without purification as a nearly white amorphous powder ; on dissolving this in tartaric acid, adding socliam carbonate, and shaking with ether, the whole dissolved : on spontaneous evaporation about 60 per cent. of the rough alkaloidal mass was obtained as crystals, and 40 as non-crystal- line basic matter from the ethereal mother-liquors. The crystals thus obtained after washing with ether were stirred up with warm dilute nitric acid ; on standing and adding a little concentrated nitric acid a magma of crystals was formed, which was separated by the pump filter and mashed wit<h dilute nitric acid : from these crystals the base was regenerated by soda and ether (Specimen E). The mother- liquors of these crystals were treated with soda and ether, and the crystals that separated examined (Specimen F). Finally, Specimen E was converted into hydrobromide, the salt recrjstallised, and the base regenerated by soda and ether (Specimen G).

The numbers obtained with all seven of these specimens are practi- cally identical : each sample was anlzydrons when air-dry.

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

3 92 WRIGHT AND LTJFF ON THE

Specimen (A) 0,2770 gram gave 0.6440 CO, and 0,1845 HzO,

), (B) 0.2580 ,, gave 0.6010 CO, and 0.1745 H20. ), (C) 0.2600 ), ,) 0.60445 CO, and 0.1735 H,O.

0.01-285 N ; by platinum salt, 0.0910 Pt.

0.3555 ), gold salt gave 0.0730 Au.

0.5670 ,, burnt with soda, lime gave by tikrntilon

0.6780 gram gold salt gave 0.1380 &I.

0.4705 , 7 gold salt gave 0.0965 ALL

0.5965 ,, gold salt gave 0.1230 Au.

7 , (D) 0.2755 ), gave 0-642.5 CO, and 0.1850 H20.

,, (E) 0.2960 ,7 gave 0.6920C0, and 0.1985 H,O.

7 , (F) 0,2775 ,. 7 , 0,6500 CO, and 0,1850 H,O. 0.3360 ,, 7 7 07840 CO, and 0.2365 H,O. 0.1940 ,, 7 7 0,0395 hu.

), (F) 0-5340 ,) gold salt gave 0,1095 Au. ,, (G) 0.3035 ,, gave 0.7060 COz and 0.2055 H20.

0.5235 ), gold salt gave 0.1060 Au. 0.3495 ,, burnt with soda lim% gave by titration,

0.00799 1J ; by platinum salt, 0.056 Pt.

I n free base. ITii gold salt. S pecinicn. Carbvn. Hy drogcn. Nitiwgen. Gold.

A ...... 63.41 7.40 - 20.53 I3 ...... 63.52 7-51 - - C ...... 63.41 7.41 { ;::; m55

F { g;; 7-82* -

G ...... 63.4% 7-52 {i::: } 20.24

D ...... 63.60 7.45 - 20.51. E ...... 63.76 7.45 - 30.62

7.41 - 20.36 20.50 ......

-- i -.. 63-58 7.50 2-27 20.44

The constancy of the numbers obtained with tbese different fractions apparently excludes the possibility of their being mixtnres of two different bases, and hence 1-enders i t improbable that they consisted of two bases, C,,H,NO,, and C33Ha,N0,,, mixed in about equivalent pro- portions ; for the results obtained with aconitine and pseudaconitine indicate that had this been the case the fractionations would have more or less completely separated these constituents. Such a, mixture,

* This combustion was made in the old-fashioned way by mixing with oxide of copper ; the others were all done by the brcech-loading process, the substance to be tumt being introduced in a platinum boat, and the combustion finished in a stream of oxygen.

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

ALEALOIDS OF THE ACONITES. 393

however, would very closely correspond with the numbers found, inas - much as it would require as follows :-

Calculated for CsH45NOll + C33H43N010 = C66H9sN2021- Found.

Carbon in base ............. 63.67 63.58 Hydrogen ,, ............ 7.07 7.50

Gold in gold salt.. .......... 20.39 20.44 Nitrogen ,, ............ 2.25 2.2 7

Moreover, had the substances examined been mixtures of two bases, C33H45NOll and C33Ha3NOlo, related as aconitine and apo-aconitine or as pseudaconitine and apo-pseudaconitine, prolonged heating with con- centrated tartaric acid solution should have converted the mixtum wholly into C33H&NO](), requiring carbon 64-60, hydrogen 7.01, nitro- gen 2.28, Au in gold salt 20.57; but as shown below (§ 2) no change whatever in composition was thus produced, no increase in carbon percentage being caused by the treatment : hence, since no simple mono-nitrogenous formula agrees well with the average numbers found, and since the formula, Cr,6H88N2021, expresses them perfectly, it results that in all probability. this formula expresses the true compo- sition of the single base isolated. It is noticeable that a substance of this composition might be supposed t o be formed fiom a base, C33H4,N012. by the removal of water as follows :-

and that this hypothetical parent base, C33Hi,N012, only differs from aconitine, C33H43N01Sr by H,. The results detailed below (§ 4) as to the action of benzoic anliydride on the crystallised base isolated as above described, and the nature of its saponification-products (9 3), viz., beuzoic acid, and a base containing H, more than apo-aconine, go far to indicate that this view of its formation, if not absolutely correct, is not far from the truth : as stated in the Appendix, however, at- tempts to isolate the hypothetical parent base, C33H4,N012, by treating Japanese roots with alcohol not acidulated by any acid a t all, so as to avoid as far as possible dehydrating action, did not lead to this result, only the base, C6,HmNzOZl, being thus obtained.

I n order to avoid circumlocution, it is proposed to refer to the c r p tallised base actually isolated, C66H88Nz0z1, as Japaconitifie, and to its saponification-product (§ 3) as Japacolzine. Should, however, the existence of the hypothetical parent base, C33H47N012, be hereafter sub- stantiated, and the formation of C6sH8,Nz0,1 from it by dehydration as above be proved, it perhaps might be more convenient to term the parent base japaconitine, and the derivative " sesqui-apo- jnpaconitinc,'!

V0.L. XYXV. 2 E

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

394 WRIGHT AND LUFF ON THE

when the saponification-product would become " apo-japaconine " (vide § 3 and 4 and Appendix, conclusion).

The seven specimens of japaconitine above described melted in capillary tubes at temperatures lying between 184" and 186" corrected in each case; or from I" to 2" higher than aconitine tested side by side, and sensibly a t the same temperature as apo-aconitine. I n Part I, by an uncorrected error of the press, 189" is given as the melting point of aconitine, instead of 183-184".

Japaconitine hydro bromide crptallises, like aconitine hydrobromide, with 2$H20 per C, present.

1.0925 gram of air-dry hydrobromide from the first batch of roots (the salt from which specimen B was prepared) lost at 100" 0.0685 gram = 6.27 per cent.

0.8575 gram of the salt from which specimen C was prepared lost 0.0560 = 6-53 per cent.

1.0240 gram of the salt from which specimen G was prepared, lost 0*0620 == 6-05 per cent.

Calculated 'for c66H88Nz~21, 2HBr, 5H20 = 6.02 per cent.

§ 2. Action of Concentruted Tartaric Acid Sotution om Japaconitine,

It has been shown in Parts I1 and 111, that when aconitine and psendaconitine are heated for some hours with concentrated tar- taric acid solution to loo", the elements of water are removed, and apo-derivatives formed. Japaconitine (Specimen (3) was heated to 100" for eight hours with a large excess of nearly saturated tartaric .acid solution; on treatmeEt with sods and ether, a base crystallised precisely resembling japaconitine in all respects, and yieldhg on com- bustion precisely the same numbers as the original substance ; where- fore no dehydration had taken place.

(1.) 0.2750 gram gave @6370 COz and 0.1820 €LO after conversion into crystallised nitrate, filter-pumping, and regenerating by soda and ether.

(11.) G.2470 gram gave 0.5735 CO, and 0.1645 H,O.

Calculated for Original substance. C@H%N202,. Specimen G. I. 11.

Carbon . . .. . . 63.67 63.44 63.17 63.32 Hydrogen . . . . 7.07 7.52 7.35 7.40

The melting point was unaltered.

$ 3. Action of Saponifying Agents om Japccioodine.

On heating japaconitine with alcoholic potash saponification rapidly takes place, being complete at tbe end of a few hours ; by evaporating

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

ALKALOIDS O F THE ACONITES. 395 off the alcohol, treating the residue with dilute sulphuric acid and ether, and allowing the ethereal solution to evaporate spontaneously, benzoic acid with a small quantity of resinous feebly acid bye-product is obtained, just as with aconitine (Part 111).

0.880 gram from first batch of roots worked up gave of benzoic acid containing a little resinous matter, 0.1730: on titration with deci- normal soda %'his corresponded to 0.1713 C7H,02.

1.9665 gram from second batch of roots gave 0.4410 gram of benaoic acid containing resinous matter ; by titration this corresponded to 0.412 C7H602.

Calculated benzoic acid per Pound. 100 parts of japaconitine. By titration. By weighing.

19.6 19.5 19.6 - 20.9 22.4

This benzoic acid agreed irt all respects with ordinary benzoic acid ; it melted at 120.5", and gave a silver salt of which

0.2120 gram gave 0.1000 Ag = 47.17 per cent. Calculated for C,H,AgOa = 47.16 per cent. The complementary product was isolated just as aconine from the

corresponding substance obtained with aconitine, viz., by alkalising with sodium carbonate the liquors from which the benzoic acid had been extracted by ether, evaporation to dryness, extraction of alkalo'idal matter by alcohol, and purification of the varnish-like mass left on evaporation to dryness by chloroform. It constituted a yellowish- white friable varnish, readily soluble in water, alcohol, and chloroform, all but insoluble in ether, and exhibiting so close a resemblance to aconine in every respect, save analytical numbers, that the two bodies could be distinguished in no other way : it reduces Fehling's solution when boiled therewith.

0.2640 gram gave 0.5745 CO, and 0.1925 HaO,

Calculated. CZ6. ....... 312 59'20 H,, ...... 41 7-78 N ........ 14 2.66 Ore.. ...... 160 30.36

Pound. 59.35 8.10

Converted into mercuriodide, 0.2535 gram gave 0.1600 AgI.

Calculated for (=26H41N01Y), HI, Hg12, sound,

Iodine. ........... 34.35 3411 2 x 2

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

396 WRIGHT AND LUFF ON TEE

From these numbers it would seem that the saponification of japa- conitine is effected in accordance with the equation-

Assuming the existence of the hypothetical parent base, C33H17N012, referred to in 8 1, this might be written-

(C~H39N*o7)\ //O O.C7H,O 0

-/- 3H;O = 2C7&02 +. 2(c26H3gNo,>~oH 0 I \OH

I

( c2&N07)/0*c7H50 N O

/O.C7H6O the parent base being then ( C26H3gN07)-OH -OH

\OH.

The experiments described in the. next section lend considerable support to this view.

8 4. Action of Bmzoic A.nhyd&de on Japaconitine and Jtpacon;ine.

It has been shown in Parts I1 and I11 that by the action of benzoic anhydride on aoonitine, aconine, and pseudaconine, dibenzoylated bodies are formed represented in the case of each of the first two

substances by (Gz6H3sNO7) =O (the products being apparently /0.CiH50

\O.C,H,O /O.C7H,O

b. c7Y50 identical), and by the formula (C,H,,NO,) =O in the case of

pseudaconine ; it, therefore, might be supposed that an analogous sub- stance would be formed in the case of japaconitine; on trying the experiment, however, the product was found to be a, substance con- taining four benzoyl-groups for every C,, in the original japaconitine ; viewing japaconitine, as above, as being derived from a parent base

( C26H3gN07) by dehydration, the tetrabenzoylated body may

/O.CiHjO -OH

\OH ,0.C7H,0 - 0 C : H O

'O.Ci&O be represented as being (C&3gN07) -o:c:H:o, formed by the direct

addition of benzoic anhydride to japaconitine, thus :-

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

ALKALOIDS OF THE ACONITES. 397

Moreover, the same tetrabenzoylatea derivative appears to be pro- duced when benzoic anhydride acts on japaconine, the reaction then being :-

/OH (C26H39NO7)=0 f 3(C7H50)20 = w7H602 + \OH

/O.C7H,O - 0 C H O

( C26H39N07)-O:,:$0,. \o .C7H60

Japaconitine was heated to -100" for eight hours with :twice its weight of benzoic anhydride, containing a small amount of fluid im- purities, which rendered it liquid at 100". On adding alcohol to the product and then agitating with a large bulk of ether and some aqueous tartaric acid, a solution of an alkalo'idal tartrate was formed, the benzoic acid and impurities present and the excess of anhydkide re- maining unchanged being retained in solution in the ethek. From the taytrate thus obtained, alkalis threw down white flakes, readily soluble in ether, but not crystallising distinctly from that menstruum. Of these,

0.2770 gram dried at 100" gave 0.6825 CO, and 0.1685 HaO.

Calculated. Found. C5.4.. ................ 648 67.43 67.20 H,, ................ 59 6.14 6.75 N .................. 14 1-46 OI5 .................. 240 24.97

- -

(C,H,NO,) (O.C7H50,)* 96-1 100.00

On saponification, 0.4690 gram of this base gave 0.2415 gram of benzoic acid, containing a little resinous matter ; on t,itration this neutralised soda equivalent to 0.235 C7Ha6O2.

Found. Calculated. By weighing. By titration.

Benzoic acid. ....... 50.78 51.49 50.11

This benzoylated derivative did not crystallise from alcohol or ether, On stirring nor did it form readily crystallisable salts with acids.

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

398 WRIQHT AND LUFF ON THE

with dilute nitric acid, a very insoluble nitrate was formed, which appeared indistinctly crystalline under the microscope. It exhibited close similarity to benzoyl apo-aconitine ; in a capillary tube it began to soften between 130" and 140", but did not melt thoroughly until a temperature higher than 160" was attained, no distinct melting point being noticeable.

I n order to see if the same substance is obtainable on benzoylating japaconine, $his base was treated with benzoic anhydride, &c., just as above described ; this base finally obtained perfectly resembled that from japaconitine in all respects.

0.2360 gram gave 0.581 C 0 2 and 0.145 HzO. Calculated. Found.

Carbon.. ........ 67-43 67-11 Hydrogen ...... 6.14 6.82

0.4860 gram, saponified with alcoholic potash, gave 0.2540 gram of benzoic acid containing a little resinous matter ; on titration, this neutralised alkali equivalent to 0.2470 C7H,0,.

Found. Calculated. By weighing. By titration.

50.78 52.26 50.82

A marked difference thus exists between japaconitine and aconitine, in that the latter forms on benzoylating only a dibenzoyl derivative ; whilst the former gives a tetrabenzoyl derivative (per C33 in each case).

§ 5 . Noncrystalliiae Alkaloids of Japanese Aconite Roots,

The mother-liquors left on crystallising from ether the crude japa.co- nitine obtained as above described closely resembled the corresponding substance obtained from A. NapeZZus roots (Parts I and 111); the varnish thus obtained from the first batch of roots worked up gave the following numbers :-Carbon, 67.69 ; hydrogen, 7.75 ; nitrogen (by soda lime), 3.23 ; whence, as with A . Napellus, a base was apparently present of lower molecular weight than japaconitine, and coritaining a higher percentage of carbon. No crystalline substance could be ob- tained from either this specimen of varnish or the similar substance obtttined from either of the other two batches of roots examined.

The alkaline liquors, from which all alkaloids soluble in ether had been washed out by repeated treatment with that menstruum, still con- tained a considerable amount of alkaloidal matter, precipitable by mercuriodide of potassium. On treating the precipitate suspended in alcohol with sulphuretted hydrogen, evaporating, dissolving in water, and precipitating with sodium carbonate, a large quantity of flocculent

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

ALKALOIDS OF THE ACONITES. 399

basic matter was thrown down apparently identical with the amor- phous base from the ethereal mother-liquors of japaconitine; the sodium carbonate filtrate, on evaporation t o dryness and treatment with alcohol yielded. a small quantity of amorphous basic matter, insoluble in water, with some amount of a base readily soluble in water and chloroform, and apparently identical with jaqaconine. The quantity of arnorphms alkalojid obtained from the mercuriodide precipitate corresponded to about 20 grams, or 0.14 per cent. of the weight of the roots employed, and b n c c was nearly equal to the amorphous nlkalojids obtained from the ethsreal mother-liquors,

I n each case examined, all the crystallisable alkaloid present in the concentrated extract obtained from the roots was dissdved onb by four or five successive treatments with ether ; the amorphous base or bases present appear to be retained in alkaline fluids much more energeti- cally than japaconitine, so that prolonged treatment with ether fails t o dissolve out the whole, although a portion is thus extracted. In this respect the amorphous bases resemble morphine when dissolved in caustic potash, or cotarnine dissolved in sodium carbonate or dilute caustic soda ; agitation with ether (and certain other solvents) then only removes a fraction of the dissolved alkalo'id..

APPEND 1%

By C. R. ALDER WRIGET and 8. E, MER'KE, Dariielk Scholar, King's College.

TEE results above described indicate that each of the two different batches of Japanese aconite root examined contained one and only one crystallisable alkalojid, the substance finally obtained being in every case identical, no matter which batch or what fraction was examined. In ewh instance the roots were originally worked up by percolation with alcohol acidulated with tartaric acid in the proportion of one pa.rt of acid to 100 of root; i t would seem 6 priori not a t all impos- sible that the tartaric acid thus introduced might act on the alkalo'id during the evaporation down of the alcoholic percolate, the result pro- bably being (judging from t,he action of tartaric acid on aconitine and yseudaconitine) removal d the elements of water without any saponi- fication being effected ; in other words, it is not unlikely that the roots originally contained yhat has been. above referred to as the " hypo- ttietical parent base," C33H17NOLz, and that this became dehydrated forming C66H8PN&, its sesqui-apo-derivative, daring the process of extraction.

In the hope of isolating the unaltered base, C3&NO12, probably originally present, a third batch of roots was worked up, but without any acid at all being employed to acidulate the alcohol used ; 1 ccvt. of

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

400 WRIGHT AND MENKE ON THE

roots (about 50 kilos.) were percolated by Messrs. Hopkins and Williams with plain alcohol ; the percolate, condensed to about 12 gallons by evaporation, was sent to us and the alkaloids contained isolated as described above, viz., by exposure to air for some days to remove most of remaining alcohol, addition of water, filtration, treatment with sodium carbonate and ether, and agitation of the ethereal extract with tartaric acid solution. From the crude tartrates thus obtained, the crystallised base was isolated by treatment with soda and ether, spon- taneous evaporation, and separation of the crystals 6hus produced from the resinoid base accumulating in the mother-liquors by filter-pumping and washing with ether. After metbodical crystallisation, there were ultimately obtained about 50 grams of crystallised base and 55 grams of resinoid base from the mother-liquors, or about 0.10 per cent. of crystals and 0.11 per cent. of varnish-like bases, or 0.21 per cent. in all. As previously indicated by Paul and Kingzett, and as found with the first batch examined, this yield is considerably superior to that obtained with a good sample (2 cwts.) of A. Napellus roots (Part I), which gave about 0.03 per cent. of crgstallised aconitine and 0.04 per cent. amorphous bases, or 0.07 per cent. in all of alkaloids soluble in ether. From these results, it may he fairly inferred that the Japanese mots are considerably richer in crystallisable as well as total alkalojids than ordinary A . NnpelZus roots ; whence, since the action of japaconi- tine on the skin appears to be much the same as that of aconitine and pseudaconitine, it seems highly probable that the Japanese roots will prove a. more convenient source of crystallisable definite active alka- lo’ids than the roots now ordinarily used, the more so as japaconitine is more easily separable from the amorphous bases than is the case with pseudaconitine, which appears at present to be the active con- stituent of most of the commercial so-called “ aconitine.”*

The crystals that were thus obtained were got in three different fractions, as follows :-By spontaneous evaporation until about three- quarters of the cyystallisable alkaloid present had separated, filter- pumping, and washing with ether, a mass of crystals was obtained almost free from amorphous bases. This was dissolved in tartaric acid, pi-ecipitated with a slight excess of clear caustic soda solution, and agitated with ether sufficient to dissolve only about a quarter of the precipitate, which quickly became a mass of crystals. The whole was then filter-pumped and the residue washed with ether, and finally several times with water to remove sods salts ; the crystals thus left were marked A. The ethereal solution thus filtered from A gare on spontaneous evaporation a crop of crystals (B), identical in all respects

* Dr. T. R. Fraser, of Edinburgh, has kindly undertaken the comparative exami- nation of the physiological action of aconitine, pseudaconitine, japsconitine, and some of their derivatives.

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

ALKALOIDS OF THE ACONITES. 401

with A. Finally, the ethereal mother-liquors from which the original mass of crystals had separated, deposited on standing a further qnan- tity of crystals with much viscid alkalo’id; by thinning with ether and filter-pumping, the crystals were mostly separated from the amor- phous alkaloid; the crystals were finally purified by rubbing with dilute warm nitric acid, which at first dissolved them, and then depo- sited a crystalline nitrate. From this crystallised salt, drained on the pump-filter, and washed with dilute nitric acid, the base was isolated by soda and ether, and the crystals thus obtained were marked C.

A fourth specimen of crystals (D) was obtained as follows:-In order to see whether all the crystallisable alkalo‘ids can be practically removed from the ground roots by alcohol alone, the marc practically exhausted by plain alcohol was treated by Messrs. Hopkins and Williams with a further quantity of alcohol, slightly acidulated with sulphuric acid (about 30 grains of concentrated acid per gallon) ; the percolate was evaporated down to about a gallon, and sent to us for examinatian. On treatment in the same way as the first percolate with plain alcohol, it was found, firstly, that only a small quantity of resinous matter was present ; wherefore the plain alcohol first used had evidently dissolved out practically all t,he resinous matter from the roots. Secondly, the total amount of alkalojids soluble in ether after repeated treatments only amounted to between 2 and 3 grams, of which about half was crystalline and half amorphous ; the crystals left on separation by the filter-pump and washing with ether were re- crystallised from ether, and thus formed specimen D, identical in all respects with A, B, and C. It is thus evident that alcohol alone, without addition of any acid, will suffice to remove practically all the alkalo’ids contained in Japanese roots (and presumably, there- fore, also in A. Napellus and A. Ferolc: roots). I t is noticeable that the condensed percolate obtained with plain alcohol was distinctly acid to test paper ; whence, since inorganic acids are apt t o decompose and saponify the aconite alkalolids, and tartaric acid to dehydrate tzhem, it appears to be preferable to exhaust aconite roots with plain alcohol rather than with acidulated alcohol in manufacturing the pure crys- tallised alkaloids, which it is to be hoped will speedily supersede the amorphous and unreliable preparations of very variable potency now met with commercially under the name of (so-called) ‘( aconitine.”

The following numbers were obtained with these four specimens, A, B, C, and D. In each case the corrected melting point was almost exactly the same a s that previously found with the other specimens ; A and C melted at 185*5”, B at 183’, and D at 181’: the small quantity of specimen D obtained, and the consequent difficulty in thoroughly purifying is evidently the cause of the somewhat low melt- ing point found,

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

402 WRIGHT AXD MEPU'KE ON THE

(A,) 0,2640 gram gave 0.6165 COz, and 0.1790 H,O. 0.4090 ,, burnt with soda lime gave by titration 0.00938

nitrogen ; by conversion into Pt salt 04605 Pt. 0,7170 gPam gold salt gave 0.1495 Au.

(B.) 0.3385 ,, gave 0.7750 C 0 2 , and 0,2250 H,O. (C.) 0.3700 ,, gave 0.8620 COT, and 0.2550 H,O.

(D.) 0.36'75 ,, gave 0.8570 CO,, and 0.2540 H,O. 06420 ,, gold salt gave 0.1320 Au.

Carbon in base. IIjdrogeo. Nitrogen. Gold in gold salt.

(A) .............. 63.69 7-53 { t:;; 20.85

- 20.56 (C) . . . . . . . . . . . . . . 68.54 7.66

1 7-50 2.27 20.43 Average of 7 speci-

mens examined 63.58

- (B) . . . . . . . . . . . . . . 63.57 7.52

(D) . . . . . . . . . . . . . 63-60 - 7.68 -

previously .... ) Caiculated - for } 63.67 7.07 2.25 20.39

C66a38N,O,, * 9

It is hence evident, firstly, that only one crystallisable alkalo'id was contained in this third batch of roots ; secondly, that this alkalojid was identical with that contained in the two batches of root previously examined, and. thirdly, that precisely tho same substance resulted whether the alcohol employed mere acidulated with tartaric acid or not: in other words, theh if, as is probable, the roots originally con-

tain an alkaloid C3&7N0,2 = (C26B39N07)= '04 , this becomes

dehydrated to the sesqui-apo-derivative termed aboye japaconitine, and indicated by the formula+--

0. C,&O

G:

by the heat alone employed in evaporating off th.e alcohol, even if no tartaric acid a t all be employed to acidulate the alcohol.

The non-crystalline bases accumulating in the. ethereal mother- liquors of the first rough crystals of japaconitine obtained from this batch were examined with the following results. Carbon = 65.73, hydrogen = 8-07', nitrogen = 2.69 per cent. : benzoic acid formed on saponification with alcoholic potash = 19.1 per cent. After saponi-

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

ALKALOIDS O F THE ACONITES. 403

fication, the base produced was almost wholly dissolved by water, and closely resembled aconine. From these results, it seems to follow that the amorphous base was almost wholly of the saponifiable class, and closely related to japaconitine; in which respect it seems to differ somewhat from the amorphous bases obtained from A. Napellus (Parts 1 and III), which yielded much less beuzoic acid on saponifica- tion, and therefore presumably contained a large admixture of a non- saponifiable alkalo‘id.

In conclusion, the following deductions may be drawn from the preceding experiments :-

(1.) The aconite roofs imported from Japan appears to be tolerabIy uniform in character, and considerably richer in active crystallisable alkaloids, as well as in the non-crysialline bases, than A. NapeZZws root.

(2.) The active crystallisable alkalo’id present is, as supposed by Paul and Kingzett, different from both aconitine a d pscudaconitine, although closely allied to. both, and especially to the former.

(3.) Only one crystallisable alkaloyd could be isolated from each of three different batches of roots examined ; this alkalo’id is indicated by the formula (and not by the approximate formula at- tributed by Paul and Kirgzett, Cz9H~,N0,). (4.) This alkaloid, to which it is proposed to give the provisional

name japaconitine, breaks up on saponification iate benzoic acid, and a new base japaamine, CZ6H,,NOlo ; on treatment with benzoic anhy- dride, it forms a derivative containing four benzogl groups for every C, originally present, in this respect differing from aconitine, which only forms a dibenzoylated derivative on similar treatment. The same derivative is formed OR benxoglating japaconine. Japaconi tine and japaconine very closely resemble aconitine and acwine respectively in all their physical properties, so that save in analytical numbers and by benzoylating, their discrimination is almost impracticable.

(5.) Contrary to the statements of Paul and Kingzett, japaconitine readily forms crystallisable salts, especially with nitric, hydrochloric, and hydrobromic acids ; the hydrobromide, like that of aconitine, con- tains 2& H,O for every C3, present.

(6.) In isolating japaconitine from the roots, plain alcohol may be used instead of alcohol acidulated w i t h fartaric acid (or with a mineral acid) ; practically all the alkalo’id present is thus easily extracted. Probably the same remarks apply to other kinds of aconite roots, wherefore in all probability i t is better in such cases to use plain alcohol only for the purpose of extracting the alkalojids.

(7.) The relationships of japaconitine to its derivatives and to aconitine are conveniently expressed by regarding japaconitine as being formed by the sesqui-dehydration of an alkalo’id, C33H17N0,2

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online

404 WRIGHT AKD MENKE ON THX ALKALOIDS O F ACONITES.

(not yet isolated in an unaltered state), closely related to aconitine, as indicated by the following table :-

Jap a conitiae Ser ies.

Hypothetical parent base, /O.C,HIO -0.H

( C26H%7N07)-0.H ,

'0.H

Sesqui - apo - derivative (japaconi- tine),

0

Benzoyl-derivative (tetrabenzoyl- ated),

/O.C,H,O

\O . C, H50

Saponification product (japaco- nine),

Aconitine Series. Aconitine,

/O.C;H,O

\O.H

Apodderivative (apo-aconitine) , /O.CTH,O

(c,~H,No,)/=o \OH

Benzoyl- derivative (dibenzoyI- ated),

/o. C7H50

(Crs&,N07)=0 \0.U7H50'

Saponification product (aconine),

/OH ( C,6H35N0,)Yo,~.

\OH Apo- aconine,

Publ

ishe

d on

01

Janu

ary

1879

. Dow

nloa

ded

by T

he U

nive

rsity

of

Bri

tish

Col

umbi

a L

ibra

ry o

n 29

/10/

2014

21:

16:0

9. View Article Online